Generally, between a cabinet body and a drawer installed therein, there are drawer slides composed of sliding rails and sliding guides for easy and smooth slide of the drawer inward or outward the cabinet body. However, since sliding rails and sliding guides are usually assembled with intervals of considerable width therebetween, when a pulling or pushing force is exerted on any point of the drawer except the center of the facade of the drawer, the drawer slides bias, leading to abnormal operation and thus wear of the drawer, eventually reducing the service life of the drawer.
For remedying this problem, the inventor of the present invention proposed an invention that has been filed in China as China Patent Application No. CN200910008402. Therein, in addition to drawer slides that guide a drawable carrier to slide in or out a cabinet body, the prior art device, at two laterals of the drawable carrier, has row holes (functioning as two lateral racks) or fixed components formed with row holes that are aligned along the sliding direction of the drawable carrier, and has an engaging assembly that includes a rod having two ends equipped with gears, wherein the gears engage with the corresponding row holes on the bottom of the drawable carrier, and the rod is supported by two seats fixed to the cabinet body, which seats each has a spring to prop up the rod, so that the upward pushing force the springs exert on the rod ensures proper engagement between the gears at the to ends of the rod and the row holes.
By the technical means of the prior art-device, when the drawable carrier is drawn or pushed to slide, even if the force exerting point is not right at the center of the facade of the drawable carrier, the limitation provided by the mutually engaging gears and the row holes, which ensures the gears to move along the row holes without derailment, maintains the sliding direction of the drawable carrier without deviation. However, when the drawable carrier, especially in the case where the drawable carrier is a large drawer, is drawn or pushed at one of its lateral edge of its facade furthest from the center and thus received an extremely transversely unbalanced force, the gears are liable to escape from the row holes, causing the drawable carrier to seriously slant to one side and become aberrant. Such aberration not only brings about sliding noise, but also leads to accelerative wear of the gears and the row holes, or, even forces the two side gears to jump out of the row holes, incurring damage to the structural components.